• Journal of Korean Society of Transportation
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• v.21 no.3
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• pp.71-83
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• 2003

An arterial street control is performed for the purpose of the progression of a traffic flow using the arterial. However during the progression in the arterial, the change according to the time is one of the most representative problems occurring at a signal plan. This paper intends to efficiently operate the arterial progression by applying fuzzy logic, which is thought to be the most possible one in the inference as that of the human logic, to the traffic responsive control system. Fuzzy Logic controller is appliable to the daily human language (linguistic). can be dealt with the uncertain traffic data and is useful on planning the signal control to sensitively confront the randomly changing traffic condition. This study, based on the signal control part of the isolated intersection in "A Development of a Real-time, Traffic Adaptive Control Scheme Through VIDs"(Seong Ho. Kim. 1996). suggested the strategy for the progression control in the arterial and analyzed its effect by comparing the effect of the existing control method. In addition, the study compared each effect by using TRAF-NETSIM which is the traffic simulation software to analyze each control method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.6
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• pp.779-792
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• 1993

In a switching node or an ATM multiplexer of the ATM network, a good bandwidth utilization can be achieved by the priority control using the 1-bit(Cell Loss priority) in ATM cell header. In this paper, the mixed mechanism is proposed to make up for shortcomings of existing space priority control mechanisms and to decrease the loss probability of high priority cell and its performance is analyzed about the cell loss probability. To estimate the performance of proposed mixed mechanism, its cell loss probability is compared with those of non-priority mechanism, push-out mechanism and partial buffer sharing mechanism. The cell loss probability is analyzed using a M/D/1/N modeling and a 2-state MMPP/D/1/N modeling and also comparison between two modelings is made. To verify this result of numerical analysis, the computer simulation is performed for each mechanism using the simulation language, SIMSRIPT II.5.

• Geomechanics and Engineering
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• v.14 no.2
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• pp.141-149
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• 2018

In this paper, the creep behavior of bolted rock was analyzed by using the unconfined creep tests and the numerical results. Based on the test results, the Bolted Burgers creep model (B-B model) was proposed to clarify the creep mechanism of rock mass due to rock bolts. As to the simulation of the creep behaviour of bolted rock, a new user-defined incremental iterative format of the B-B model was established and the open-source $FLAC^{3D}$ code was written by using the object-oriented language (C++). To check the reliability of the present B-B creep constitutive model program, a numerical model of a tunnel with buried depth of 1000 m was established to analyze the creep response of the tunnel with the B-B model support, the non-support and the bolt element support. The simulation results show that the present B-B model is consistent with the calculated results of the inherent bolt element in $FLAC^{3D}$, and the convergence deformation can be more effectively controlled when the proposed B-B model is used in the $FLAC^{3D}$ software. The big advantage of the present B-B creep model secondarily developed in the $FLAC^{3D}$ software is the high computational efficiency.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.61 no.6
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• pp.851-858
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• 2012

In this paper, we design a seismic data acquisition system(SDAS) and implement it. This system is essential for development of a noble local earthquake disaster preventing system in population center. In the system, we choose a proper MEMS-type triaxial accelerometer as a sensor, and FPGA and ARM processor are used for implementing the system. In the SDAS, each module is realized by Verilog HDL and C Language. We carry out the ModelSim simulation to verify the performances of important modules. The simulation results show that the FPGA-based data acquisition module can guarantee an accurate time-synchronization for the measured data from each axis sensor. Moreover, the FPGA-ARM based embedded technology in system hardware design can reduce the system cost by the integration of data logger, communication sever, and facility control system. To evaluate the data acquisition performance of the SDAS, we perform experiments for real seismic signals with the exciter. Performances comparison between the acquired data of the SDAS and the reference sensor shows that the data acquisition performance of the SDAS is valid.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.12
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• pp.2322-2327
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• 2009

Uncertainty of power system operation increases due to complexity and facilities diversification in the power system. Therefore the importance of SCADA(Supervisory Control and Data Acquisition) system which obtain and manage the actual data in real-time is very important. Accordingly in the studies of power system analysis, the efforts to include real-time power system analysis in simulation and applications are made in many ways. The real-time communication characteristics of SCADA system is considered so as to develop the power system analysis program that matches actual system conditions. The observation and management of SCADA system is realized by Intouch which is mainly used for factory automation and PSS/E(Power System Simulator for Engineers) provides real time system data. SQL DB and Python language is used for real-time communication between the softwares. It is very comfortable to use the various functions in Intouch WindowMaker.

• Journal of Korean Society for Quality Management
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• v.22 no.1
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• pp.188-204
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• 1994

Most of computer-aided process planning(CAPP) systems have been developed to automate the process planning function. In this paper, we describe an analytical model for a CAPP system in order to improve the performance of production system in flexible manufacturing systems(FMSs) for computer intergrated manufacturing(CIM) architecture. This paper proposes an optimal process planning that minimizes the load time by minimizing the cycle time and the number of workstations using Kang and Hahm's heuristic approach so as to improve the performance of production system under the batch production of discrete products. We also perform simulation using SIMAN language to campare the line utilization of each for various product types. The proposed algorithm can be implemented in existing FMSs for on-line control of product quantity using programmable logic controllers(PLC) and communication devices.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.10
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• pp.48-60
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• 1996

This paper focuses on the necessities of interworking and dervation of the requirements of interworking system for interworking between 64 Kbps based N-ISDN (narrowband ISDN) and B-ISDN(broadband ISDN). Furthermore, the design and the implementation of IWF (interworking function) are presentd. We analyze two ISDN signalling systems, and propose the architecture of interworking system. And then we make the baisc call procedure model between N-ISDN and B-ISDN, and verify the dynamic behaviors through the reachability tree of petri net. IWF is designed and implemented for transforming the differences between the two signalling systems. The operational confirmity of th eimplemented program was confirmed by the local test method. The performance of IWF was evaluated throguh the simulation language SLAM-II. As the result of evaluation shows, we confirm that the processing delay is maintained within 3 ms under the utilization 0.9.

• Journal of the Korean Institute of Telematics and Electronics
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• v.25 no.6
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• pp.637-646
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• 1988

The CMOS physical parameters are extracted using by processing models in fabrication steps, processing parameters, fabrication disturbances, control parameters. Statistical CMOS process and device simulator is proposed to evaluate the effect of inherent fluctuations in IC fabrication. Using this simulator, we perform worst case analysis in terms of statistically independent disturbances and compare this proposed method to Monte Carlo method, previous Worst Case method. And simulation results with this proposed method are more accurate than the past worst case analysis. This package is written in C language and runs on a IBM PC AT(OPUS).

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.5
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• pp.358-363
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• 2000

In this paper, a voltage equations, a thrust force equations and kinetic equation are derived from the basic structure of a 2-phase hybrid type linear stepping motor(HLSM). And a micro-stepping method in order to eliminate effectively the resonant phenomena and to increase the positional resolution of the HLSM was proposed. The proposed micro-stepping method can divide one step into the maximum 128 micro-steps under simple control system. The dynamic characteristics of proposed micro-stepping method were analyzed by the ACSL(Advanced Continuous Simulation Language) with the voltage equations, the thrust force equations and the kinetic equation, and were measured by laser experimental system. As the result, the justice of theory was confirmed, and the resonant phenomena, the positional resolution and dynamic thrust were improved by the proposed micro-stepping method.

• Journal of Software Assessment and Valuation
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• v.17 no.1
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• pp.93-99
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• 2021

The demand for online education has rapidly increased due to the influence of COVID-19. One of the biggest challenges in engineering education is how to efficiently conduct experiments online. In this paper, for the virtual experimental system for microcontroller application that is essential for education in the field of electrical, electronic, and control engineering, we described the microcontroller functional modeling and implementation with Java language. The usefulness of the developed microcontroller module has been verified through educational field application.